On the part of a connecting bar led throughout of the housing to the outside, such as that described in FR 2 484 135 A1, an equipment-side power feeding bar can be connected in this way. The connecting bar is in this case generally arranged securely in the insulating wall of an appliance or device, which can take place for example by clamping bolts.
According to the above-mentioned FR 2 484 135 A1, the connecting bars are adapted to the different nominal currents by putting together the standard cross section of a plurality of pieces, which consist of copper or aluminum. For the highest intended nominal current, only pieces made of copper are used, while for the lowest intended nominal current only pieces of aluminum are used. For nominal currents lying in between, the connecting bars have combinations of pieces made of the two materials, for example one piece made of copper, three pieces made of aluminum.
There is also the proposal (earlier patent application with the application number DE 199 30 813.6, published as DE 199 30 813 A1) of producing connecting bars from sections of a profiled semi-finished material which include webs or ribs, which add to a cross section dependent on the nominal current to give a spacing dimension that is the same for all nominal currents. This makes it unnecessary to use different materials and a plurality of pieces.
Connecting bars of the type stated above may at the same time have a feature disclosed by DE 196 43 607 A1, that is a further projection (web, rib), which serves as an axial positioning and supporting device for the connecting bar on the wall of the housing of the appliance or device. Further fasteners are then either not required at all or only required in a simplified form. If bolts are used as such fasteners, they can engage in a nut thread, which is formed in a known way by a metallic insert nut or press-in nut located in the insulating material of the wall (DE 35 39 673 A1).
It follows from the descriptions given above that the current-carrying capacity, heat dissipation, provision of a surface for connections of power feeding bars and the absorption and transmission of static and dynamic forces are among the main tasks of the connecting bars. In addition, it is intended for it to be possible to accommodate connecting bars for different current intensities in walls with standard lead-through openings.